I was more making a joke than anything about populations shifting there. The region is kind of the agricultural hub of The United States and as agriculture has become streamlined and industrialized, people have been leaving for urban areas for a number of reasons, mainly jobs and the resources provided by larger communities. Those ghost towns kleinbl00 talks about? A large percentage of them are in The Great Plains. Every now and again, you'll see some kind of weird outlier, like Bismark North Dakota where there's an oil rush at the moment, but for the most part, there's not much going on out there. That said, I've read about proposals for letting the plains turn into even bigger swaths of wilderness than they already are, so the buffalos can roam again and America can regain some of its lost beauty. Don't ask me how that's going though, cause I honestly don't know. Edit: Wikipedia's article on rural flight is a good summary.